By: Rob Burckley, Induron Sales Representative
The Northern Kentucky Water District recently undertook a significant rehabilitation project involving two large water storage tanks. The project was managed by Semper Fi with engineering oversight by Dixon Engineering. This extensive project faced numerous challenges, including a tight timeframe and a comprehensive list of repairs.
The project challenges
Each tank was allotted only 45 days out of service, necessitating precise planning and efficient execution. Plus, due to the proximity to residential areas, partial containment was essential for applying the overcoat system to minimize disruption and ensure safety. A comprehensive list of structural and mechanical repairs was also required. Induron is proud to have specified and supplied a coating solution that could overcome these challenges and result in two restored tanks.
The coating solutions
Both the “Old State” 1-Million Gallon Leg Tank and the “Independence” 1-Million Gallon Flute tank received the exterior and interior coatings systems listed below.
The tank exteriors required a pressure wash and an overcoat system of:
- Spot application of Induron’s E-Bond 100 Penetrating Sealer
- Full coat of E-Bond
- Intermediate coat of Indurethan 6600 Plus
- Finish coat of Indurethan 6600 Plus
The tank interiors required a wet full blast SSPC-SP10 and a coating system for the bowl and sidewall of:
- Primer: Indurazinc MC-67 (2.5 – 3.5 mils DFT)
- Stripe Coat: PE-70 Epoxy (1.5 – 2.5 mils DFT)
- Topcoat: TL-70 Ceramic Epoxy (8.0 – 12.0 mils DFT)
**Total DFT:** 12.0 – 18.0 mils
The roof coating system included:
- Primer: Indurazinc MC-67 (2.5 – 3.5 mils DFT)
- Stripe Coat: PE-70 Epoxy (1.5 – 2.5 mils DFT)
- Topcoat: TL-70 Ceramic Epoxy (20.0 – 26.0 mils DFT)
**Total DFT:** 22.5 – 29.5 mils
All dry areas received a 3-coat epoxy system of PE70, and the pit piping and foundation received two coats of PE70.
Additional repairs for the “Old State” tank included:
- Replace the wet interior roof hatch.
- Install a handhold at the painter’s (bird) hatch.
- Install a riser grate.
- Replace the overflow flap gate.
- Adjust the loose sway rods.
- Tighten the loose leg anchor bolts.
- Install a wet interior ladder from the platform to the bowl.
- Install a roof handrail with a painter’s railing.
- Install a swing gate and handrail section at the top platform opening.
- Install bowl rigging couplings.
- Replace the dry interior light bulbs.
- Replace the sample tap on the fill/draw pipe
Additional repairs for the “Independence” tank included:
- Replacement of the bowl manway gasket.
- Replacement of the wet interior roof hatch.
- Replacement of the access tube roof hatch.
- Installation of a cover over the wet interior platform opening.
- Modification of the overflow discharge.
- Installation of a mud valve.
- Replacement of the fall prevention device on the wet interior ladder.
- Repair of the bowl manway ladder.
- Replacement of the roof vent with a pressure vacuum vent.
- Installation of a roof handrail with a painter’s railing.
- Installation of a swing gate at the top platform opening.
- Replacement of the sample tap on the fill/draw pipe.
- Evaluation and replacement of the light switch in the dry interior.
- Replacement of all light bulbs in the dry interior.
- Removal of the cathodic protection system. Patching of the hole in the overflow pipe inside the wet interior.
The project outcome
This project was initiated in August 2023 and completed in May 2024. While the first tank’s completion was delayed due to weather conditions and changes in project scope, the second tank was completed on schedule, demonstrating the project’s efficiency and effective problem-solving capabilities despite initial setbacks with the first tank. All in all, this tank rehabilitation project showcases the successful overcoming of significant challenges. The project’s completion within the given constraints reflects a high level of planning, execution, and commitment to quality and safety.